Patent GB-573266-A (GB)
Title: Improvements relating to the production of amidines or salts thereof
IPC: C07D213/78
Filed: 1944-01-27
Abstract: Amidines in the form of their sulphonic acid salts are produced by the reaction at an elevated temperature of (a) an ammonium salt of a sulphonic acid of the general formula R1-SO2H, wherein R1 represents an alkyl, aralkyl or aryl residue, or (b) a primary monoamine or secondary diarylamine salt of such a sulphonic acid, with a nitrile of the general formula R-CN, wherein R represents an alkyl, aralkyl, aryl or heterocyclic residue, or with a compound which affords such a nitrile under the conditions of the reaction.  The sulphonic acid salt reagent may be formed in situ from its components.  The free amidines may be liberated from their sulphonic acid salts by treatment with a base.  The products have application in chemotherapy.  Examples relate the reaction of (1) ammonium benzenesulphonate, toluene-p-sulphonate, p-nitrobenzene sulphonate, naphthalene-b -sulphonate or methanesulphonate with p-sulphonamidobenzonitrile; (2) benzenesulphonic acid with benzonitrile and sulphanilamide; (3) ammonium p-cyanobenzenesulphonate with itself by heating at 310 DEG  C.; (4) ammonium benzenesulphonate with benzonitrile; (5) ammonium p benzenesulphonate with o-, m- or p-nitrobenzonitrile; (6) ammonium benzenesulphonate with 1 : 11-dicyano-undecane with addition of picric acid to an alcoholic solution of the product to form undecane-1 : 11-di-amidine picrate; (7) ammonium benzenesulphonate (1 mol) with 4 : 41-dicyano-a  : b -diphenoxyethane (2 mols), the product being isolated as the picrate; (8) ammonium benzenesulphonate (1 mol) with 4 : 41-dicyano-a  : b -diphenoxyethane (1 mol); (9) ammonium benzenesulphonate with p-cyanophenyl methyl sulphone, the product being isolated as the hydrochloride; (10) ammonium benzenesulphonate with p-cyanophenyl ethyl sulphone; (11) ammonium benzenesulphonate with p-cyanodiphenyl sulphone; (12) ammonium benzenesulphonate with pp1-dicyanodiphenyl, the product being isolated as the dihydrochloride; (13) ammonium benzenesulphonate with a -naphthonitrile; (14) ammonium benzenesulphonate with b -naphthonitrile; (15) ammonium benzenesulphonate with a -cyanopyridine; (16) toluidine benzenesulphonate or aniline benzenesulphonate (1 mol) with benzonitrile (1 mol); (17) p-toluidine benzenesulphonate or aniline benzenesulphonate (2 mols) with benzonitrile (1 mol); (18) p-nitraniline benzenesulphonate with benzonitrile; (19) p-toluidine benzenesulphonate with benzyl cyanide; (20) methylamine benzenesulphonate with benzyl cyanid with isolation of the amidine as the reineckate; (21) benzylamine benzenesulphonate with benzyl cyanide; (22) benzenesulphonic acid with benzonitrile and diphenylamine; (23) ammonium benzenesulphonate with benzamide, the benzamidine being isolated as the trichloracetate.  p - Cyanophenyl - methyl - or ethyl - sulphone is obtained by heating phenyl-methyl- or ethyl-sulphone-p-carboxylic acid respectively with benzenesulphonamide.  p - Cyanodiphenyl - sulphone is similarly obtained from diphenylsulphone-p-carboxylic acid.  Phenyl - methyl - sulphone - p - carboxylic acid is obtained by oxidation of p-tolyl-methyl-sulphone with potassium permanganate.